1. Field of the Invention
With reference to the fields of art established in the United States Patent and Trademark Office to which this invention pertains, attention is invited to the general class titled "Electric Heating" (Class 219) and more particularly to the subclass thereunder titled, "welding-process" (subclass 137R). Also of interest in that class is the subclass titled "cylinders-helical seam" (subclass 62) and "container" (subclass 64). Also of interest is the class titled "Heat Exchanger" (Class 165) and the subclass "conduit within or conforming to panel or wall structure--wall forms enclosure" (subclass 169).
2. Description of the Prior Art
The use of heat and cold in the processing of compositions, chemicals, plastics and the like is well known. Many of these processing operations are performed in vessels having either inner or outer conduit wrapping or both. Vessels having such conduit wrapping are shown in my U.S. Pat. No. 3,318,378 issued May 9, 1967. To the extent pertinent the disclosures of that patent and my U.S. Pat. No. 3,452,568 are incorporated by reference into the present Application.
In the processing of compounds vessels which have auxiliary heating and cooling systems are often used. Such heating with present processing may utilize steam up to 750 p.s.i. and then with rapid cooling the temperature in the compound may be brought to the low teens Farenheit. The heating and cooling cycle causes an expansion and contraction particularly in the wrapping welded in place on the walls of the vessels and also welded to itself. The rapid change in temperature is usually greater in the wrapping than in main vessel or container and often causes cracks to develop in the welds. Those cracks, of course, must or at least should be repaired before high pressure steam or pressurized fluid can be or is continued to be directed to flow in the wrapping.
The present invention is directed toward the reinforcement of the end-to-end joints of succeeding lengths of wrapping on a vessel. These reinforcements are applicable to either transverse or angled cut wrapping.
Three patents were noted and broadly pertain to the idea presented in this Application. U.S. Pat. No. 1,700,319 to KJEKSTAD issued Jan. 29, 1929, shows an exterior wrapping for a conduit construction and as an exterior or an auxiliary wrapping reinforces the joint of the pipe or conduit either seamless or lap welded. That wrapping is in the nature of a sleeve, and the joint is indicated as a transverse cut normally squared to the axis of the pipe. Also showing a reinforcement of a joint of a pipe is U.S. Pat. No. 1,853,549 to CLARK issued Apr. 12, 1932. That patent shows a serpentine lap piece added to the pipe at a transverse butt section of the pipe. A weld providing reinforcement to a sloped wall is shown in U.S. Pat. No. 3,842,237 to UJIIE issued Oct. 15, 1974, which indicates the desirability of making an inclined groove joint to attack walls of material together. The identified patents do not show or suggest any slanted cut in a wrapping such as is hereinafter more fully described. In these and any other prior art teachings known to me there is no showing of a slanted or beveled cut in the wrapping whereby the expansion or contraction from heating or cooling can be accommodated by that slanted cut at an end-to-end wrapping joint. An interior and exterior reinforcing of this joining helps spread the shock load over a larger portion of the applied wrapping of a vessel.